Style .feed-icon with an icon, like in Bartik

Hello, you can use this code:
.feed-icon {
background: url(../../../../misc/feed.svg) no-repeat;
overflow: hidden;
text-indent: -9999px;
display: block;
width: 16px;
height: 16px;
}

The current CSS in 8.4 is:

.feed-icon {
    background: url(/core/misc/feed.svg) no-repeat;
    overflow: hidden;
    text-indent: -9999px;
    display: block;
    width: 16px;
    height: 16px;
}

Neither #2 nor #3 are acceptable long term solutions.

Both are relative paths, #2 being relative to where this project is installed and #3 relative to the DOCROOT of the site (which may be in a sub-folder/path of the domain).

Yes, it would be nice if there were a relevant glyphicon that could be used instead... but there isn't and the upcoming BS4 has removed glyphicons altogether.

I really don't like the idea of adding another image to this project.

The only image we currently provide (in 8.x-3.x only BTW) is the required asterisk SVG #2768439: CSS of required field is broken in chrome . Replace the asterisk by a SVG .

Core removed the theme function which allowed us to target it specifically and moved to a CSS only solution #2152217: Remove theme_form_required_marker() from the theme system - use CSS instead. Ironically, this "solution" has been plagued by many different issues (e.g. #2274631: Form required marker "\204E" is broken in Google Chrome 35 / Internet Explorer 9) and they have finally realized that the entire thing has been a big mistake #2921627: Do not use a CSS-only required marker in forms per WCAG 2.0.

These kinds of things are what makes maintaining projects like this a PITA, especially when it's just a base theme and not intended to hit every stylistic use case.

This at least shows you the default text as a fallback until a preferred style in a sub-theme is applied.

I don't think this will make it into this project, especially with #2852156: Move "overrides" source files and generated CSS to separate project on my mind more and more.